THE TERMS OF HAPPINESSPeriodically in "The Science of Happiness," we'll feature a unit called "The Terms of Happiness," in which we define terminology that's important to the core concepts of that week.

This is our first, and perhaps most elementary, "Terms of Happiness" unit, covering some of the terms scientists use to define happiness.

Happiness: This is a big one. Most of us probably don’t believe we need a formal definition of happiness--we know it when we feel it, and we often use the term to describe a range of positive emotions, including joy, pride, contentment, and gratitude.

But as Dacher suggested in his previous video, to understand the causes and effects of happiness, researchers first need to define it. Many of them use the term interchangeably with “subjective well-being,” which they measure by simply asking people to report how satisfied they feel with their own lives and how much positive and negative emotion they’re experiencing. In her 2007 book The How of Happiness, positive psychology researcher Sonja Lyubomirsky elaborates, describing happiness as “the experience of joy, contentment, or positive well-being, combined with a sense that one’s life is good, meaningful, and worthwhile.”

That definition resonates with the focus of this course and the approach the Greater Good Science Center takes toward happiness: It captures the fleeting positive emotions that come with happiness, along with a deeper sense of meaning and purpose in life—and suggests how these properties of happiness complement each other.

Here are some of the terms that describe what scientists measure when they set out to measure happiness. You'll encounter them across studies of happiness featured in this course.

Life satisfaction: A general assessment that, as a whole, one's life is good and worth living. Researchers usually measure life satisfaction by using the Satisfaction with Life Scale, developed by University of Illinois professor Ed Diener and colleagues.

Positive affect: A technical term to describe the experience of feeling a positive emotion, such as joy, love, or amusement. As Dr. Lyubomirsky notes above, positive affect is an important ingredient to happiness and is sometimes used synonymously with happiness, though it generally

refers to a fleeting emotional state rather than an enduring way of being. It is often measured using the Positive and Negative Affect Schedule (PANAS).

Subjective well-being: As mentioned above, researchers often use this term interchangably with happiness, perhaps because it sounds more precise and scientific. It refers to the way people evaluate their lives, in terms of both their global life satisfaction and emotional states--i.e., it is often assessed by measuring life satisfaction and positive affect. It is strongly tied to positive health.